The present disclosure relates generally to electronic circuits, and more specifically to magnetic components for electronic circuits.
Magnetic components, such as inductor and transformer assemblies, use windings around a magnetic core to create magnetic flux inside the core. The resulting magnetic fields then regulate current flow and/or voltage in the circuit, either alone or in conjunction with other components. Core saturation and thermal limits often dictate the size and weight of the core. In traditional designs, it is often assumed that the flux is evenly distributed inside the core, making the cross-sectional area of the core an important design parameter. In reality, due to the dimension of the core, the flux tends to flow in a path with the least magnetic reluctance (similar to electrical resistance).
However, with conventional cores, reluctance is not uniformly distributed, which increases the likelihood of saturation in certain parts of the core and results in underutilization of the full volume of the cores. In a traditional inductor construction with a monolithic toroidal core, the flux is concentrated around the inner radius. Some simulations show the flux around the inner radius of a monolithic toroidal core with a large number of windings to be about 34 times the flux near the outer radius. This will result in saturation of the inner portion of the core before the outer portion of the core can be fully utilized.